Git is a fast, scalable, distributed revision control system with an unusually
rich command set that provides both high-level operations and full access to
internals.

See gittutorial(7) to get started, then see giteveryday(7) for a
useful minimum set of commands. The Git User’s Manual[1] has a
more in-depth introduction.

After you mastered the basic concepts, you can come back to this page to learn
what commands Git offers. You can learn more about individual Git commands
with "git help command". gitcli(7) manual page gives you an
overview of the command-line command syntax.

A formatted and hyperlinked copy of the latest Git documentation can be viewed
at https://git.github.io/htmldocs/git.html.

Prints the synopsis and a list of the most
commonly used commands. If the option --all or -a is given then
all available commands are printed. If a Git command is named this option will
bring up the manual page for that command.

Other options are available to control how the manual page is displayed. See
git-help(1) for more information, because git --help ... is
converted internally into git help ....

-C <path>

Run as if git was started in
<path> instead of the current working directory. When multiple
-C options are given, each subsequent non-absolute -C
<path> is interpreted relative to the preceding -C
<path>.

This option affects options that expect path name like --git-dir and
--work-tree in that their interpretations of the path names would be
made relative to the working directory caused by the -C option. For
example the following invocations are equivalent:

Pass a configuration parameter to the command.
The value given will override values from configuration files. The
<name> is expected in the same format as listed by git config
(subkeys separated by dots).

Note that omitting the = in git -c foo.bar ... is allowed and sets
foo.bar to the boolean true value (just like [foo]bar would in a
config file). Including the equals but with an empty value (like git -c
foo.bar= ...) sets foo.bar to the empty string which git config
--bool will convert to false.

--exec-path[=<path>]

Path to wherever your core Git programs are
installed. This can also be controlled by setting the GIT_EXEC_PATH
environment variable. If no path is given, git will print the current
setting and then exit.

--html-path

Print the path, without trailing slash, where
Git’s HTML documentation is installed and exit.

--man-path

Print the manpath (see man(1)) for the
man pages for this version of Git and exit.

--info-path

Print the path where the Info files
documenting this version of Git are installed and exit.

-p, --paginate

Pipe all output into less (or if set,
$PAGER) if standard output is a terminal. This overrides the
pager.<cmd> configuration options (see the "Configuration
Mechanism" section below).

--no-pager

Do not pipe Git output into a pager.

--git-dir=<path>

Set the path to the repository. This can also
be controlled by setting the GIT_DIR environment variable. It can be an
absolute path or relative path to current working directory.

--work-tree=<path>

Set the path to the working tree. It can be an
absolute path or a path relative to the current working directory. This can
also be controlled by setting the GIT_WORK_TREE environment variable and the
core.worktree configuration variable (see core.worktree in
git-config(1) for a more detailed discussion).

--namespace=<path>

Set the Git namespace. See
gitnamespaces(7) for more details. Equivalent to setting the
GIT_NAMESPACE environment variable.

--super-prefix=<path>

Currently for internal use only. Set a prefix
which gives a path from above a repository down to its root. One use is to
give submodules context about the superproject that invoked it.

--bare

Treat the repository as a bare repository. If
GIT_DIR environment is not set, it is set to the current working
directory.

--no-replace-objects

Do not use replacement refs to replace Git
objects. See git-replace(1) for more information.

--literal-pathspecs

Treat pathspecs literally (i.e. no globbing,
no pathspec magic). This is equivalent to setting the
GIT_LITERAL_PATHSPECS environment variable to 1.

--glob-pathspecs

Add "glob" magic to all pathspec.
This is equivalent to setting the GIT_GLOB_PATHSPECS environment
variable to 1. Disabling globbing on individual pathspecs can be done
using pathspec magic ":(literal)"

--noglob-pathspecs

Add "literal" magic to all pathspec.
This is equivalent to setting the GIT_NOGLOB_PATHSPECS environment
variable to 1. Enabling globbing on individual pathspecs can be done
using pathspec magic ":(glob)"

--icase-pathspecs

Add "icase" magic to all pathspec.
This is equivalent to setting the GIT_ICASE_PATHSPECS environment
variable to 1.

--no-optional-locks

Do not perform optional operations that
require locks. This is equivalent to setting the GIT_OPTIONAL_LOCKS to
0.

Although Git includes its own porcelain layer, its low-level commands are
sufficient to support development of alternative porcelains. Developers of
such porcelains might start by reading about git-update-index(1) and
git-read-tree(1).

The interface (input, output, set of options and the semantics) to these
low-level commands are meant to be a lot more stable than Porcelain level
commands, because these commands are primarily for scripted use. The interface
to Porcelain commands on the other hand are subject to change in order to
improve the end user experience.

The following description divides the low-level commands into commands that
manipulate objects (in the repository, index, and working tree), commands that
interrogate and compare objects, and commands that move objects and references
between repositories.

Indicates a tree, commit or tag object name. A
command that takes a <tree-ish> argument ultimately wants to operate on
a <tree> object but automatically dereferences <commit> and
<tag> objects that point at a <tree>.

<commit-ish>

Indicates a commit or tag object name. A
command that takes a <commit-ish> argument ultimately wants to operate
on a <commit> object but automatically dereferences <tag> objects
that point at a <commit>.

<type>

Indicates that an object type is required.
Currently one of: blob, tree, commit, or
tag.

<file>

Indicates a filename - almost always relative
to the root of the tree structure GIT_INDEX_FILE describes.

These environment variables apply to all core Git commands. Nb: it is
worth noting that they may be used/overridden by SCMS sitting above Git so
take care if using a foreign front-end.

GIT_INDEX_FILE

This environment allows the specification of
an alternate index file. If not specified, the default of
$GIT_DIR/index is used.

GIT_INDEX_VERSION

This environment variable allows the
specification of an index version for new repositories. It won’t affect
existing index files. By default index file version 2 or 3 is used. See
git-update-index(1) for more information.

GIT_OBJECT_DIRECTORY

If the object storage directory is specified
via this environment variable then the sha1 directories are created underneath
- otherwise the default $GIT_DIR/objects directory is used.

GIT_ALTERNATE_OBJECT_DIRECTORIES

Due to the immutable nature of Git objects,
old objects can be archived into shared, read-only directories. This variable
specifies a ":" separated (on Windows ";" separated) list
of Git object directories which can be used to search for Git objects. New
objects will not be written to these directories.

Entries that begin with `"` (double-quote) will be interpreted
as C-style quoted paths, removing leading and trailing
double-quotes and respecting backslash escapes. E.g., the value
`"path-with-\"-and-:-in-it":vanilla-path` has two paths:
`path-with-"-and-:-in-it` and `vanilla-path`.

GIT_DIR

If the GIT_DIR environment variable is
set then it specifies a path to use instead of the default .git for the
base of the repository. The --git-dir command-line option also sets
this value.

GIT_WORK_TREE

Set the path to the root of the working tree.
This can also be controlled by the --work-tree command-line option and
the core.worktree configuration variable.

GIT_NAMESPACE

Set the Git namespace; see
gitnamespaces(7) for details. The --namespace command-line
option also sets this value.

GIT_CEILING_DIRECTORIES

This should be a colon-separated list of
absolute paths. If set, it is a list of directories that Git should not chdir
up into while looking for a repository directory (useful for excluding
slow-loading network directories). It will not exclude the current working
directory or a GIT_DIR set on the command line or in the environment.
Normally, Git has to read the entries in this list and resolve any symlink
that might be present in order to compare them with the current directory.
However, if even this access is slow, you can add an empty entry to the list
to tell Git that the subsequent entries are not symlinks and needn’t be
resolved; e.g.,
GIT_CEILING_DIRECTORIES=/maybe/symlink::/very/slow/non/symlink.

GIT_DISCOVERY_ACROSS_FILESYSTEM

When run in a directory that does not have
".git" repository directory, Git tries to find such a directory in
the parent directories to find the top of the working tree, but by default it
does not cross filesystem boundaries. This environment variable can be set to
true to tell Git not to stop at filesystem boundaries. Like
GIT_CEILING_DIRECTORIES, this will not affect an explicit repository
directory set via GIT_DIR or on the command line.

GIT_COMMON_DIR

If this variable is set to a path,
non-worktree files that are normally in $GIT_DIR will be taken from this path
instead. Worktree-specific files such as HEAD or index are taken from
$GIT_DIR. See gitrepository-layout(5) and git-worktree(1) for
details. This variable has lower precedence than other path variables such as
GIT_INDEX_FILE, GIT_OBJECT_DIRECTORY...

Only valid setting is "--unified=??"
or "-u??" to set the number of context lines shown when a unified
diff is created. This takes precedence over any "-U" or
"--unified" option value passed on the Git diff command line.

GIT_EXTERNAL_DIFF

When the environment variable
GIT_EXTERNAL_DIFF is set, the program named by it is called, instead of
the diff invocation described above. For a path that is added, removed, or
modified, GIT_EXTERNAL_DIFF is called with 7 parameters:

path old-file old-hex old-mode new-file new-hex new-mode

where:

<old|new>-file

are files GIT_EXTERNAL_DIFF can use to read
the contents of <old|new>,

<old|new>-hex

are the 40-hexdigit SHA-1 hashes,

<old|new>-mode

are the octal representation of the file
modes.

The file parameters can point at the user’s working file (e.g.
new-file in "git-diff-files"), /dev/null (e.g.
old-file when a new file is added), or a temporary file (e.g.
old-file in the index). GIT_EXTERNAL_DIFF should not worry about
unlinking the temporary file --- it is removed when GIT_EXTERNAL_DIFF
exits.

For a path that is unmerged, GIT_EXTERNAL_DIFF is called with 1
parameter, <path>.

For each path GIT_EXTERNAL_DIFF is called, two environment variables,
GIT_DIFF_PATH_COUNTER and GIT_DIFF_PATH_TOTAL are set.

A number controlling the amount of output
shown by the recursive merge strategy. Overrides merge.verbosity. See
git-merge(1)

GIT_PAGER

This environment variable overrides
$PAGER. If it is set to an empty string or to the value
"cat", Git will not launch a pager. See also the core.pager
option in git-config(1).

GIT_EDITOR

This environment variable overrides
$EDITOR and $VISUAL. It is used by several Git commands when, on
interactive mode, an editor is to be launched. See also git-var(1) and
the core.editor option in git-config(1).

GIT_SSH, GIT_SSH_COMMAND

If either of these environment variables is
set then git fetch and git push will use the specified command
instead of ssh when they need to connect to a remote system. The
command-line parameters passed to the configured command are determined by the
ssh variant. See ssh.variant option in git-config(1) for
details.

+ $GIT_SSH_COMMAND takes precedence over $GIT_SSH, and is
interpreted by the shell, which allows additional arguments to be included.
$GIT_SSH on the other hand must be just the path to a program (which
can be a wrapper shell script, if additional arguments are needed).

+ Usually it is easier to configure any desired options through your personal
.ssh/config file. Please consult your ssh documentation for further
details.

GIT_SSH_VARIANT

If this environment variable is set, it
overrides Git’s autodetection whether
GIT_SSH/GIT_SSH_COMMAND/ core.sshCommand refer to
OpenSSH, plink or tortoiseplink. This variable overrides the config setting
ssh.variant that serves the same purpose.

GIT_ASKPASS

If this environment variable is set, then Git
commands which need to acquire passwords or passphrases (e.g. for HTTP or IMAP
authentication) will call this program with a suitable prompt as command-line
argument and read the password from its STDOUT. See also the
core.askPass option in git-config(1).

GIT_TERMINAL_PROMPT

If this environment variable is set to
0, git will not prompt on the terminal (e.g., when asking for HTTP
authentication).

GIT_CONFIG_NOSYSTEM

Whether to skip reading settings from the
system-wide $(prefix)/etc/gitconfig file. This environment variable can
be used along with $HOME and $XDG_CONFIG_HOME to create a
predictable environment for a picky script, or you can set it temporarily to
avoid using a buggy /etc/gitconfig file while waiting for someone with
sufficient permissions to fix it.

GIT_FLUSH

If this environment variable is set to
"1", then commands such as git blame (in incremental mode),
git rev-list, git log, git check-attr and git
check-ignore will force a flush of the output stream after each record
have been flushed. If this variable is set to "0", the output of
these commands will be done using completely buffered I/O. If this environment
variable is not set, Git will choose buffered or record-oriented flushing
based on whether stdout appears to be redirected to a file or not.

If this variable is set to "1", "2" or "true"
(comparison is case insensitive), trace messages will be printed to stderr.

If the variable is set to an integer value greater than 2 and lower than 10
(strictly) then Git will interpret this value as an open file descriptor and
will try to write the trace messages into this file descriptor.

Alternatively, if the variable is set to an absolute path (starting with a
/ character), Git will interpret this as a file path and will try to
write the trace messages into it.

Unsetting the variable, or setting it to empty, "0" or
"false" (case insensitive) disables trace messages.

GIT_TRACE_FSMONITOR

Enables trace messages for the filesystem
monitor extension. See GIT_TRACE for available trace output
options.

GIT_TRACE_PACK_ACCESS

Enables trace messages for all accesses to any
packs. For each access, the pack file name and an offset in the pack is
recorded. This may be helpful for troubleshooting some pack-related
performance problems. See GIT_TRACE for available trace output
options.

GIT_TRACE_PACKET

Enables trace messages for all packets coming
in or out of a given program. This can help with debugging object negotiation
or other protocol issues. Tracing is turned off at a packet starting with
"PACK" (but see GIT_TRACE_PACKFILE below). See
GIT_TRACE for available trace output options.

GIT_TRACE_PACKFILE

Enables tracing of packfiles sent or received
by a given program. Unlike other trace output, this trace is verbatim: no
headers, and no quoting of binary data. You almost certainly want to direct
into a file (e.g., GIT_TRACE_PACKFILE=/tmp/my.pack) rather than
displaying it on the terminal or mixing it with other trace output.

Note that this is currently only implemented for the client side of clones and
fetches.

GIT_TRACE_PERFORMANCE

Enables performance related trace messages,
e.g. total execution time of each Git command. See GIT_TRACE for
available trace output options.

GIT_TRACE_SETUP

Enables trace messages printing the .git,
working tree and current working directory after Git has completed its setup
phase. See GIT_TRACE for available trace output options.

GIT_TRACE_SHALLOW

Enables trace messages that can help debugging
fetching / cloning of shallow repositories. See GIT_TRACE for available
trace output options.

GIT_TRACE_CURL

Enables a curl full trace dump of all incoming
and outgoing data, including descriptive information, of the git transport
protocol. This is similar to doing curl --trace-ascii on the command
line. This option overrides setting the GIT_CURL_VERBOSE environment
variable. See GIT_TRACE for available trace output options.

GIT_LITERAL_PATHSPECS

Setting this variable to 1 will cause
Git to treat all pathspecs literally, rather than as glob patterns. For
example, running GIT_LITERAL_PATHSPECS=1 git log -- '*.c' will search
for commits that touch the path *.c, not any paths that the glob
*.c matches. You might want this if you are feeding literal paths to
Git (e.g., paths previously given to you by git ls-tree, --raw
diff output, etc).

GIT_GLOB_PATHSPECS

Setting this variable to 1 will cause
Git to treat all pathspecs as glob patterns (aka "glob"
magic).

GIT_NOGLOB_PATHSPECS

Setting this variable to 1 will cause
Git to treat all pathspecs as literal (aka "literal" magic).

GIT_ICASE_PATHSPECS

Setting this variable to 1 will cause
Git to treat all pathspecs as case-insensitive.

GIT_REFLOG_ACTION

When a ref is updated, reflog entries are
created to keep track of the reason why the ref was updated (which is
typically the name of the high-level command that updated the ref), in
addition to the old and new values of the ref. A scripted Porcelain command
can use set_reflog_action helper function in git-sh-setup to set its
name to this variable when it is invoked as the top level command by the end
user, to be recorded in the body of the reflog.

GIT_REF_PARANOIA

If set to 1, include broken or badly
named refs when iterating over lists of refs. In a normal, non-corrupted
repository, this does nothing. However, enabling it may help git to detect and
abort some operations in the presence of broken refs. Git sets this variable
automatically when performing destructive operations like git-prune(1).
You should not need to set it yourself unless you want to be paranoid about
making sure an operation has touched every ref (e.g., because you are cloning
a repository to make a backup).

GIT_ALLOW_PROTOCOL

If set to a colon-separated list of protocols,
behave as if protocol.allow is set to never, and each of the
listed protocols has protocol.<name>.allow set to always
(overriding any existing configuration). In other words, any protocol not
mentioned will be disallowed (i.e., this is a whitelist, not a blacklist). See
the description of protocol.allow in git-config(1) for more
details.

GIT_PROTOCOL_FROM_USER

Set to 0 to prevent protocols used by
fetch/push/clone which are configured to the user state. This is useful
to restrict recursive submodule initialization from an untrusted repository or
for programs which feed potentially-untrusted URLS to git commands. See
git-config(1) for more details.

GIT_PROTOCOL

For internal use only. Used in handshaking the
wire protocol. Contains a colon : separated list of keys with optional
values key[=value]. Presence of unknown keys and values must be
ignored.

GIT_OPTIONAL_LOCKS

If set to 0, Git will complete any
requested operation without performing any optional sub-operations that
require taking a lock. For example, this will prevent git status from
refreshing the index as a side effect. This is useful for processes running in
the background which do not want to cause lock contention with other
operations on the repository. Defaults to 1.

GIT_REDIRECT_STDIN, GIT_REDIRECT_STDOUT,
GIT_REDIRECT_STDERR

Windows-only: allow redirecting the standard
input/output/error handles to paths specified by the environment variables.
This is particularly useful in multi-threaded applications where the canonical
way to pass standard handles via CreateProcess() is not an option
because it would require the handles to be marked inheritable (and
consequently every spawned process would inherit them, possibly
blocking regular Git operations). The primary intended use case is to use
named pipes for communication (e.g. \\.\pipe\my-git-stdin-123).

Two special values are supported: off will simply close the corresponding
standard handle, and if GIT_REDIRECT_STDERR is 2>&1,
standard error will be redirected to the same handle as standard output.

GIT_PRINT_SHA1_ELLIPSIS (deprecated)

If set to yes, print an ellipsis
following an (abbreviated) SHA-1 value. This affects indications of detached
HEADs ( git-checkout(1)) and the raw diff output (git-diff(1)).
Printing an ellipsis in the cases mentioned is no longer considered adequate
and support for it is likely to be removed in the foreseeable future (along
with the variable).

More detail on the following is available from the Git concepts chapter of
the user-manual[2] and gitcore-tutorial(7).

A Git project normally consists of a working directory with a ".git"
subdirectory at the top level. The .git directory contains, among other
things, a compressed object database representing the complete history of the
project, an "index" file which links that history to the current
contents of the working tree, and named pointers into that history such as
tags and branch heads.

The object database contains objects of three main types: blobs, which hold file
data; trees, which point to blobs and other trees to build up directory
hierarchies; and commits, which each reference a single tree and some number
of parent commits.

The commit, equivalent to what other systems call a "changeset" or
"version", represents a step in the project’s history, and
each parent represents an immediately preceding step. Commits with more than
one parent represent merges of independent lines of development.

All objects are named by the SHA-1 hash of their contents, normally written as a
string of 40 hex digits. Such names are globally unique. The entire history
leading up to a commit can be vouched for by signing just that commit. A
fourth object type, the tag, is provided for this purpose.

When first created, objects are stored in individual files, but for efficiency
may later be compressed together into "pack files".

Named pointers called refs mark interesting points in history. A ref may contain
the SHA-1 name of an object or the name of another ref. Refs with names
beginning ref/head/ contain the SHA-1 name of the most recent commit
(or "head") of a branch under development. SHA-1 names of tags of
interest are stored under ref/tags/. A special ref named HEAD
contains the name of the currently checked-out branch.

The index file is initialized with a list of all paths and, for each path, a
blob object and a set of attributes. The blob object represents the contents
of the file as of the head of the current branch. The attributes (last
modified time, size, etc.) are taken from the corresponding file in the
working tree. Subsequent changes to the working tree can be found by comparing
these attributes. The index may be updated with new content, and new commits
may be created from the content stored in the index.

The index is also capable of storing multiple entries (called
"stages") for a given pathname. These stages are used to hold the
various unmerged version of a file when a merge is in progress.

Git was started by Linus Torvalds, and is currently maintained by Junio C
Hamano. Numerous contributions have come from the Git mailing list <
git@vger.kernel.org[5]>.
http://www.openhub.net/p/git/contributors/summary gives you a more
complete list of contributors.

If you have a clone of git.git itself, the output of git-shortlog(1) and
git-blame(1) can show you the authors for specific parts of the
project.